1.3.5- trinitrobenzene synthesis

Trinitrobenzene (TNB) (2) is a more powerful explosive than TNT. However, the direct synthesis of TNB from benzene is not practical and the need for an indirect route for its synthesis makes its manufacture too expensive for use as a practical high explosive. 

The synthesis of 1,3,5-trinitrobenzene (TNB) from the direct nitration of m-dinitrobenzene is very difficult. Desvergnes reported a 71 % yield of TNB (2) on treatment of m-dinitrobenzene (32) with a large excess of mixed acid composed of anhydrous nitric acid and 60 % oleum at a reaction temperature of 110 °C for several days. Similar results are also reported from other... 

Trinitrobenzene is present in crude TNT manufactured by mixed acid nitration and results from methyl group oxidation followed by decarboxylation." In fact, a convenient method for the synthesis of 1,3,5-trinitrobenzene involves oxidation of 2,4,6-trinitrotoluene with a solution of sodium dichromate in sulfuric acid, followed by decarboxylation of the resulting 2,4,6-trinitrobenzoic acid in boiling water." 1,3,5-Trinitrobenzene is prepared from 2,4,6-trinitro-m-xylene by a similar route." 2,4,6-Trinitroanisole can be prepared from the... 

Borsche synthesized both 1,2,4- and 1,2,3-trinitrobenzenes by treating Af-hydroxy-2,4-dinitroaniline and Al-hydroxy-2,6-dinitroaniline, respectively, with fuming nitric acid. The method is very convenient for the synthesis of such substrates because the starting materials are readily obtainable from the reaction of hydroxylamine with the appropriate dini-trochlorobenzene isomer. Borsche also synthesized 1,2,3,5-tetranitrobenzene (60%)... 

A synthesis of hexanitrobenzene (55) has been reported which involves hydroxyamino oxidation. Although no experimental details of this procedure are given the synthesis is reported to start from partial reduction of 1,3,5-trinitrobenzene (2) to l,3,5-tris(hydroxyamino)benzene... 

The effect which amino functionality has on the thermal and impact sensitivity of polyni-troarylenes (Section 4.8.1.4) makes amination by VNS a method with much future potential for energetic materials synthesis. Other carbon, nitrogen, oxygen and sulfur nucleophiles can displace aromatic hydrogen examples with 1,3-dinitrobenzene and 1,3,5-trinitrobenzene are extensive. 

All reported syntheses of TATB to date involve the nitration of substrates containing leaving groups which are subsequently replaced by amino groups. The current industrial synthesis of TATB (14) involves the nitration of 1,3,5-trichlorobenzene (33) to 1,3,5-trichloro-2,4,6-trinitrobenzene (34) followed by reaction with ammonia in toluene under pressure. Both nitration and amination steps require forced conditions with elevated temperatures. 

TNT has been used as a starting material for the synthesis of 2,3,4,5,6-pentani-troaniline (see Section 4.8.4), and hence, for the synthesis of hexanitrobenzene via oxidation with peroxydisulfuric acid, and l,3,5-triamino-2,4,6-trinitrobenzene (TATB) via nucleophilic displacement with ammonia. " " ... 

Similar routes have been used for the synthesis of other polynitrophenylenes. 1,3,5-Tris(2,4,6-trinitrophenyl)-2,4,6-trinitrobenzene (160) is synthesized from the reaction of 1,3,5-trichloro-2,4,6-trinitrobenzene with three equivalents of picryl chloride in the presence of activated copper powder in refluxing mesitylene. " 2,2",4,4, 4",6,6, 6"-Octanitro-m-terphenyl (161) has been synthesized from picryl chloride and l,3-dichloro-4,6-dinitrobenzene. ... 

Laval and Vignane reported the synthesis of the nitrotriazole (124) from the reaction of 3-nitro-1,2,4-triazole with 3,5-diamino-l-chloro-2,4,6-trinitrobenzene. The nitrotriazole (124) is a useful secondary high explosive, exhibiting high performance and a low sensitivity to impact. 

Navy. 1983. Synthesis and properties of trisubstituted trinitrobenzenes TATB analogs. Silver Spring, MD Naval Surface Weapons Center. Document no. AD A131619. 

Problem 11.52 Available organic starting materials for synthesizing the pairs of compounds below are PhH, PhMe, and PhNO,. Select the compound in each pair whose synthesis is more expensive and explain your choice, (a) p-C,H4(N02)2 and m-C,H4(N02)2, (b) m-nitrotoluene and p-nitrotoluene, (c) 2,4.6-trinitrotoluene (TNT) and 1,3,5-trinitrobenzene, (d) ffi-C H4Cl2 and p-C H4Clj. ... 

Step 1 Synthesis of l-fhioro-3,5-diamino-2,4,6-trinitrobenzene (intermediate 1)... 

The reactions between i-dinitrobenzene or 1,3,5-trinitrobenzene, aryl halides, and copper(I) oxide in quinoline 17-19, 21) provide a simple synthesis of nitrobiphenyls uncontaminated by symmetrical biphenyls. These couplings may be related to the Ullmann reaction, the decarboxylative coupling of benzoic acids with aryl halides, and the preparation of ethers from phenols 165). Although no intermediates... 

The commercial dinitrophenol mixture is produced by heating phenol with dilute sulfuric acid, cooling the product, and then nitrating while keeping the temperature below 50 °C, or by nitrating with a mixed acid under careful temperature control (Sax and Lewis 1987). 2,3-, 2,5-, and 3,4-DNP are prepared by nitration of m-nitrophenol. 3,5-DNP is prepared by the replacement of one nitro group by methoxyl in 1,3,5-trinitrobenzene and demethylation of the dinitroanisole by anhydrous aluminum chloride. 2,6-DNP is prepared by sulfonation and nitration of o-nitrophenol (Harvey 1959). 2,6-DNP is also produced as a byproduct in the synthesis of 2,4-DNP by way of 2,4-dinitrochlorobenzene. 

Although many other explosives and explosives-related compounds exist, only the data for 2,4,6-trinitrotoluene (TNT) and its breakdown products, the cyclic nit-ramines (RDX and HMX), tetryl, trinitrobenzene, and nitroglycerin will be reviewed in this chapter. Two dinitrotoluene isomers are also included, as they are still used as explosives in addition to being side-products of TNT synthesis. 

Synthesis.—Af-Phenylamides can be prepared from carboxylic acids by first esteri-fying the acid with 2-fluoro-1,3,5-trinitrobenzene followed by displacement of the ester group with aniline.This mild method is successful for a good range of acids, giving consistently high yields of the amide. A direct, high-yield conversion of esters into AW-disubstituted amides is by reaction with dimethylaluminium amides, which similarly convert lactones into hydroxyamides. ... 

Scheme 12 General electrochemical mechanism for the synthesis of l-butyl-2,4,6-trinitrobenzene derivatives. 88114 acts as both nucleophile and reducting agent...

Olah, G. A. Lin, H. C. Synthetic methods and reactions. XL Convenient direct preparation of 1,3,5-trinitrobenzene from m-dmitrobenzene by nitration with nitronium tetrafluoroborate in lluorosulfuric acid solution. Synthesis 1974, 444-445. 

Following the synthesis reported last year of 3,5,7-trinitro-l-aza-adam-antane from 1,3,5-trinitrobenzene the reaction has now been extended to TNT to give (23). Transformation products are reported of (24), prepared... 

SCHEME 11.46 Synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene via double VNS amination of 2,4,6-... 

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